1. Technical Field
The present invention relates to optical communications, and more particularly to multidimensional turbo product codes and generalized low-density parity-check codes with component Reed-Solomon codes for optical transmission.
2. Description of the Related Art
Network providers already consider 100 Gb/s per dense wavelength-division multiplexing (DWDM) channel transmission for future optical networks. The bit-error ratio (BER) performance of such systems is degraded significantly due to intra-channel fiber nonlinearities, polarization mode dispersion (PMD), and chromatic dispersion. In order to overcome those challenges, novel advanced techniques and devices in modulation, detection, coding and signal processing are required. The development of a novel powerful forward error correction (FEC) scheme suitable for beyond 100 Gb/s transmission and 100 Gb/s Ethernet is of high importance. To keep the BER quality for those systems comparable to that of a standard RS(255, 239) FEC scheme operating at 40 Gb/s, an FEC scheme providing at least 4 dB improvement in coding gain is necessary.
The soft iteratively decodable codes such as, for example, turbo-product codes (TPCs) and LDPC codes, are excellent candidates for use in high-speed optical communications. Although those schemes provide excellent performance improvement, they require soft bit reliabilities, and as such are still not implementable at data rates above 100 Gb/s.